During the encounter, Garner raised both hands in the air and told the officers not to touch him. Seconds later, a video shows an officer behind him grab the 350-pound man in a choke hold and pull him to the sidewalk, rolling him onto his stomach.

"I can't breathe! I can't breathe!" Garner said repeatedly, his cries muffled into the pavement.

The cause of Garner's death was "compression of neck (choke hold), compression of chest and prone positioning during physical restraint by police," said Julie Bolcer, a spokeswoman for the medical examiner's office. The death was ruled a homicide.

Acute and chronic bronchial asthma, obesity and hypertensive cardiovascular disease were listed as contributing conditions in a controversial death that sparked anti-police demonstrations and calls for a federal investigation.

Douglas Auer, a spokesman for the Richmond County district attorney's office, said the investigation into the death was continuing.

"We await the issuance of the official death certificate and the autopsy report," he said in a statement.

There was no immediate reaction from Garner's family.

The video of the incident showed the Staten Island man lying on the ground motionless after he was taken down by a group of officers. An asthmatic, Garner was later declared dead at a nearby hospital, according to CNN affiliate WCBS. Police said he suffered a heart attack and died on the way to the hospital.

"This is a terrible tragedy that occurred ... A terrible tragedy that no family should have to experience," New York Mayor Bill de Blasio said after the death, calling the video of the incident "very troubling."

Garner, a grandfather with six children, had a lengthy criminal history, including more than 30 arrests, and had been previously arrested for selling untaxed cigarettes in May, according to police.

But demonstrators in New York called the police response during his arrest excessive and criminal.

On July 19, Garner's friends and family rallied with the Rev. Al Sharpton in Harlem, demanding a full investigation into Garner's death, according to WCBS.

Officer Daniel Pantaleo, who is seen on the video choking Garner, was put on modified assignment and stripped of his badge and gun as the New York Police Department continues to investigate the incident, WCBS reported. The choke hold tactic is prohibited by the NYPD.

Two EMTs and two paramedics also were suspended without pay, according to Erika Hellstrom, vice president of development at Richmond University Medical Center.

In a statement, Patrolmen's Benevolent Association President Patrick J. Lynch called Pantaleo's reassignment "a completely unwarranted, kneejerk reaction for political reasons." He said the move "effectively pre-judges this case and denies the officer the very benefit of a doubt that has long been part of the social contract that allows police officers to face the risks of this difficult and complex job."

Police Commissioner William Bratton ordered an extensive review of the NYPD's training procedures after Garner death.

After a two-hour meeting with NYPD Training Commissioner Ben Tucker last week, Bratton ordered a "top to bottom review of all the training that this department provides to its personnel, specifically focusing on force, how do we train our officers for a takedown, how do we train them to use the various levels of force that they're authorized to use."

"I would anticipate that coming out of this effort that there will be a re-training of every member of the New York City Police Department in the weeks, months and potential years ahead," Bratton said.